Influences Of Different Fertilization Methods Under Border Irrigation On Spatial And Temporal Distribution Of Soil Water And Nitrogen In Winter Wheat-summer Maize Rotation Cropland

Fertigation,which is regarded as the number one technology in modern agriculture,is mainly applied in micro-irrigation and sprinkling irrigation so far.While in our country,surface irrigation is the leading irrigation method.Achieving the major breakthrough of integration of water and fertilizer in surface irrigation is of great significance to the development of modern agriculture.In this study,winter wheat and summer maize rotation was regard as the research object in Huang-Huai-Hai area.By studying the effects of irrigation technical parameters and fertilization methods on the spatial and temporal distribution of soil water and nitrogen under border irrigation,the appropriate irrigation technical parameters and fertilization methods were explored to improve the use efficiency of water and nitrogen.This study will provide a basis for the optimization of border irrigation technical scheme and the application of fertigation technology in border irrigation.Based on the field experiment study and analysis,the conclusions are as follows:1.The influence of fertilization methods,timing and inflow rates on soil water variation and its spatial distribution uniformity is not significant,while the influence on soil nitrate nitrogen is obvious.2.Under the same inflow rate,the variation degree of spatial distribution of soil nitrate in all of the fertigation treatments was less than the traditional fertilization mode,and the spary distribution uniformity along the border length of soil nitrate in all of the fertigation treatments was also better than the traditional fertilization mode.3.2 days after applying water and fertilizer,the spatial distribution variability of soil water was far less than that of soil nitrate.Increasing the inflow rate appropriately can improve the distribution uniformity of soil water along border length direction.4.2 days after irrigation,the change of the storage efficiency of soil water and nitrate in the effective root zone in different treatments is not obvious.5.10 days after irrigation,the spatial variation of soil water in effective crop zone is decreasing,and then become stabilized.While the spatial variation of soil nitrate is not obvious.6.Under the condition of this experiment,the border strip fertilization with the inflow rate of 4 L/(s·m)and with applying fertilizer as water advanced at 33% of the border length can produce high proportion of soil water and nitrogen accumulation in the effective root zone and provide optimal distribution uniformity along length direction,and then form a spatial homogeneity distribution of soil water and nitrate which is beneficial for crop absorption.